Cartridge-actuated fastener-driving tools

ABSTRACT

Simple and trouble-free feeding of a strip-form cartridge magazine into a fastener-driving tool is achieved by providing a displaceable member for this purpose alone which is unconnected with other tool functions. The active member is effectively a spring-loaded tube which is fitted into the hand-grip portion of the tool, normally projects outwardly therefrom to a distance equal to the cartridge spacing along the magazine strip, and through which the magazine is fed.

ite States Schneider atent 1 CARTRlDGE-ACTUATED FASTENER-DRKVHNG TOOLS [75] inventor: Fritz Schneider, Burgbemheim,

Germany [73] Assignee: Impex-Essen GmbH, Ansbach,

Germany 22 Filed: Jan. 13,1972

21 Appl. NO.I 217,563

[30] Foreign Application Priority Data Jan. 14, 1971 Germany P 21 01 499.3

[52] US. Cl. 227/10, 227/8 [51] Int. Cl. B25c 1/14 [58] Field of Search 227/8, 9, 10, 11, 227/107, 136

[56] References Cited UNITED STATES PATENTS 3,554,425 1/1971 Oesterle 227/10 2/l97l Seghezzi et al. 227/l0 6/1972 Pomeroy 227/10 Primary Examiner-Granville Y. Custer, Jr. Assistant ExaminerH. P. Smith, Jr. Attorney-Karl F. Ross [57] ABSTRACT Simple and trouble-free feeding of a strip-form cartridge magazine into a fastener-driving tool is achieved by providing a displaceable member for this purpose alone which is unconnected with other tool functions.

The active member is effectively a spring-loaded tube which is fitted into the hand-grip portion of the tool, normally projects outwardly therefrom to a distance equal to the cartridge spacing along the magazine strip, and through which the magazine is fed.

9 Claims, 3 Drawing Figures CARTRIDGE-ACTUATED FASTENER-DRIVING TOOLS BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to cartridge-actuated fastenerdriving tools for explosively inserting studs, bolts, pins, or other like fasteners.

The invention is concerned with cartridge-actuated fastener-driving tools comprising a tool casing, a barrel which is axially displaceable in the casing and which carries a plunger which is arranged to be explosively thrust down the barrel to drivingly insert a fastener, a cartridge chamber at the rear end of the barrel on the axis thereof, a breech member mounted in the tool casing adjacent to the cartridge chamber, firing pin means within the breech member and movable relative thereto, a magazine feed channel extending through a hand-grip portion of the tool casing and between the rear end of the barrel and the breech member, the feed channel being arranged to receive a strip-form magazine loaded with cartridges arranged serially in succession along the strip, the magazine being provided with a plurality of detent means spaced along its length at distances equal to the cartridge spacing, and displaceable transfer means engageable with said detent means in order to advance the magazine in step-wise manner through the feed channel.

2. Description of Prior Art Cartridge-actuated fastener-driving tools of the above-mentioned type are known. By the use of existing strip-form cartridge magazines such fastenerdriving tools can be handled easily, particularly when used for rapid successional firing. However, it is of importance with such tools that they should have troublefree feeding of the cartridges and of the magazine strip. In certain of the known tools however such a requirement cannot be unconditionally guaranteed. This is often because in certain of the known tools the feeding of the magazine strip is coupled with other tool functions, for example with the firing or triggering mechanism or with an auxiliary device for simultaneously pulling back the plunger into its ready-to-fire position. Furthermore, in one such known fastener-driving tool the transfer means engaging the detent teeth of the magazine strip is formed as a double-armed pivotable lever which co-operates with the barrel mounted displaceably in the tool casing in such a manner that the barrel must be forced forwards and then drawn back again for each advancement of the magazine strip, this movement also causing a firing pin spring to be compressed. In this latter tool, when a fastener is inserted into the barrel there is the danger that the magazine strip will be moved automatically and unnoticed into the ready-to-fire position and that by an untimely displacement of the firing pin a cartridge could be detohated.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a cartridge-actuated fastener-driving tool operating with a strip-form cartridge magazine which has a comparatively simple construction to permit trouble-free feeding of the magazine strip and which also has a high degree of built-in safety.

This is achieved in accordance with the present invention by a cartridge-actuated fastener-driving tool comprising a tool casing, a barrel which is axially displaceable in the casing and which carries a plunger which is arranged to be explosively thrust down the barrel to drivingly insert a fastener, a cartridge chamber at the rear end of the barrel on the axis thereof, a breech member mounted in the tool casing adjacent to the cartridge chamber, firing pin means within the breech member and movable relative thereto, a magazine feed channel extending through a hand-grip portion of the tool casing and between the rear end of the barrel and the breech member, the feed channel being arranged to receive a strip-form magazine loaded with cartridges arranged serially in succession along the strip, the magazine being provided with a plurality of detent means spaced along its length at distances equal to the cartridge spacing, and displaceable transfer means engageable with said detent means in order to advance the magazine in step-wise manner through the feed channel, the transfer means being formed as a manually actuated member which is alone provided for the advancement of the magazine and which has a portion thereof projecting from the hand-grip portion of the tool casing.

In this way the step-wise feeding of the cartridge magazine is effected completely independently of the other usual tool functions and with the greatest possible safety directly by a direct actuation of the transfer means.

The transfer means preferably comprises a sleeve member which is open at each end and surrounds the magazine and which is mounted for limited axial displacement in the lower part of the feed channel, one end of the sleeve member normally projecting outwardly from the hand-grip portion of the tool casing to a distance substantially equal to the feed stroke of the magazine. The sleeve member may be arranged to be forced into the hand-grip portion of the tool casing against the action of a spring, with its inner end linked to further spring means which engages with the detent means of the magazine strip.

Preferably, the spring engaging the actuating sleeve member is a helical compression spring mounted in the feed channel, the spring being seated at its one end against a shoulder in the feed channel and at its other end being supported at the inner end of the sleeve member.

The further spring means may be formed as an extension of the compression spring by the latter being bent first radially outwardly and then axially up to and beyond the inner end of the compression spring.

Alternatively, an additional separate strip spring element may be used as said further spring means which has its outer end clamped between the sleeve member and the helical compression spring.

BRIEF DESCRIPTION OF THE DRAWINGS In order that the invention may be fully understood, a preferred embodiment of cartridge-actuated fastenerdriving tool in accordance with the invention will now be described by way of example and with reference to the accompanying drawings, in which:

FIG. 1 is a vertical longitudinal sectional view through the tool;

FIG. 2 is a cross-sectional view taken along the line ll-Il of FIG. 3; and,

FIG. 3 is a top plan view of the tool of FIG. 1, with the right-hand half of the figure showing the tool cut away at the level of the barrel.

DESCRIPTION OF THE PREFERRED EMBODIMENT The drawings show a cartridge-actuated fastenerdriving tool comprising a casing 2 provided with a hand-grip 1 and with a barrel 3 which is mounted for axial displacement within the casing. A muzzle-piece 4 is detachably secured to the front end of the barrel 3, for example by means of a bayonet connection. A fastener 6, for example in the form of a stud carrying a stabilizing disc or roundel 5, is arranged to fit into the muzzle-piece 4. A plunger 7 which serves to drive the fastener 6 into a receiving surface is fitted within the bore 3 of the barrel 3 and at its rear end is enlarged to form a heat 7' which is slidable along the bore of the barrel. The front end of the plunger 7 projects into the muzzle-piece 4 and may rest against the rearwardly facing head 6' of the stud 6. A cartridge chamber 8 is provided in the rear part of the barrel 3. In its underside the barrel 3 is provided with a longitudinal slot 9 therethrough. A detachable arrester bolt 10 extends up through the slot 9 and projects partially into the bore 3 of the barrel 3. The bolt 10 may be secured by a screw connection for example. By the use of arrester bolts 10 which are shaped differently at their ends 10' which provide the check surface it is possible to vary the size of the expansion chamber 3" and in conse quence to affect the driving power of the tool.

In the rear part of the tool casing is positioned a breech ring 11 which has a longitudinal bore 11 therein. A firing block 12 provided with a firing pin 12' is fitted within the bore 11 in the breech ring and a spring 13 acts upon one end face of the firing block. The firing block 12, as is shown more particularly in FIG. 3, is fitted with a transverse pin 15 which is biased outwardly by a spring 14. The transverse pin 15 is mounted for limited displacement in a transverse bore 12" in the firing block 12. A slide rail 16 is secured to the rear end of the barrel 3 and is suitably shaped towards its rear end to engage the transverse pin 15. Thus, when the barrel 3 is forced back, the slide rail 16 also forces the pin 15 rearwardly and the firing block 12 is displaced in to its rearward position in which the firing block spring 13 is compressed. When the trigger 18 is pulled a slide rod 19 at the rear of the trigger is forced rearwardly and the inclined rear face of the rod 19 strikes against a trip pin 20 provided with corresponding sloping surfaces. Movement of the trip pin 20 causes the transverse pin 15 to be forced inwardly into the bore 12" provided that the tool is pressed firmly against the surface into which the fastener is to be driven, with the result that the firing block 12 is impelled forwards by the release of the compressed spring 13. A compression spring 21 engages against the slide rod 19 to bias the trigger 18 into its forward, normal position.

A feed channel 22 which serves to receive a stripform magazine 24 loaded with cartridges 23 arranged singly in series along its length extends up through the handgrip 1 and between the rear end of the barrel and the breech ring 11. The magazine strip 24 is provided, as shown in FIG. 2, with detent means in the form of teeth 24' extending along one or both sides of the strip and with the tooth spacing equal to the cartridge spacing.

A displaceable transfer device engages with the teeth 24' in order to advance the magazine strip 24 in a stepwise manner. This transfer device comprises an actuating sleeve 25 which is open at both ends and which is mounted for limited axial displacement in the lower part of the feed channel 22. The outer end 25 of the sleeve 25 projects downwardly from the hand-grip 1 by an amount approximately equal to the displacement stroke of the sleeve. The sleeve 25 can be forced inwardly into the hand-grip 1 against the action of a spring 26, and the inner end 27 of a spring element 2'7 which abuts against the inner end 25 of the sleeve engages with the teeth 24' of the magazine strip 24. The spring 26 is formed as a helical compression spring which is positioned in the feed channel 22 and which is seated at its one end against a shoulder 22' formed in the feed channel and at its other end against the inner end 25" of the actuating sleeve 25. The spring element 27 may be formed as an extension of the compression spring 26, in which case the helical compression spring 26 may be extended at its lower end, first being bent radially outwardly and then being bent back to extend axially beyond the inner end of the spring 26 and finally being angled at its inner end 27' so that it is able to engage behind the radial surfaces 24" of the teeth 24'. However, it is easier to construct the tool if the spring element 27, as shown, is formed as a separate additional spring element which is bent at its inner end 27' and similarly at its outer end 27" where it is clamped between the sleeve 25 and the spring 26. In order to limit the displacement stroke of the actuating sleeve 25 a recess 28 is formed in the sleeve and into the recess projects a check pin 29 secured to the handgrip 1. In order to prevent undesired reverse movement of the magazine strip 24 after each forward feed movement a spring clip 30 projects into the upper end of the feed channel 22 and grips the teeth 24' of the magazine strip 24. The spring clip 30, as shown particularly in FIGS. 1 and 3, is fitted into a suitable recess 31 formed in the upper surface of the tool casing 2.

The method of operation and the manner of use of the tool is as follows. Firstly, the stud 6 or other fastener to be driven into a receiving surface is inserted into the muzzle-piece 4 of the barrel into the position shown in FIG. 1, and then a strip-form cartridge magazine 24 which has been removed from its packing is inserted through the actuating sleeve 25 and into the feed channel 22 in such manner that the trailing end 24" of the strip terminates flush with the outer end 25 of the actuating sleeve 25. By this means the first cartridge 23 is brought in an orderly way into its ready-tofire position in front of the firing pin 12. If then the muzzle-piece 4 of the tool is pressed hard against the surface into which the fastener is to be driven, the corresponding rearward displacement of the barrel 3 against the action of the recoil spring 17 forces the cartridge chamber 8 in the rear end of the barrel back over the cartridge 23'. Simultaneously, by means of the slide rail 16 and the transverse pin 15 the firing block 12 is forced back and the firing spring 13 is compressed. Then, with the tool pressed firmly against the surface into which the fastener is to be driven, actuation of the trigger 18 causes the transverse pin 15 to be forced into its bore and the firing block 12 is impelled forwards to cause detonation of the cartridge 23' and thus an explosive forward movement of the plunger 7. The stud 6 is in this way driven into the receiving surface. After the tool is lifted away from the surface into which the fastener has been driven the barrel 3 is thrown forward by a corresponding jerky movement of the tool op'erator. Thus, the empty cartridge case is drawn from the cartridge chamber 8 since the magazine strip 24 is held fast in a T-shaped cross-section groove in the breech ring 11. Finally, the barrel 3 reaches the end of its movement when the end of the slot 9 adjacent to the rear of the barrel strikes against the arrester bolt 10. In this way, the plunger 7 is returned to its initial position in relation to the barrel 3.

For the next fastener driving operation, after pushing back the barrel 3 and plunger 7 into the position shown in FIG. 1, the next stud 6 is then inserted into the muzzle-piece 4. Then, by pressing in the actuating sleeve 25 the magazine strip 24 is advanced one step corresponding to the cartridge spacing by virtue of the spring element 27 and of its operative inner end 27. The end 27 of the spring element engages behind the tooth 24", but on the other hand the spring clip 30 slides over the inclined surface 24" of the tooth and only grips the strip again at the end of the feed stroke when it engages behind the succeeding tooth indicated in FIG. 2 by the reference 24". In this way, the next cartridge 23" is brought into the ready-to-fire position and can be detonated after the barrel 3 has again been forced back into its rear position.

I claim:

1. A cartridge-actuated fastener-driving tool comprising a tool casing, a barrel which is axially displaceable in the casing and which carries a plunger which is arranged to be explosively thrust down the barrel to drivingly insert a fastener, a cartridge chamber at the rear end of the barrel on the axis thereof, a breech member mounted in the tool casing adjacent to the cartridge chamber, firing pin means within the breech member and movable relative thereto, a magazine feed channel extending through a hand-grip portion of the tool casing and between the rear end of the barrel and the breech member, said feed channel being arranged to receive a strip-form magazine loaded with cartridges arranged serially in succession along the strip, the magazine being provided with a plurality of detent means spaced along its length at distances equal to the cartridge spacing, and displaceable transfer means engageable with said detent means in order to advance the magazine in step-wise manner through the feed channel, said transfer means being formed as a manually actuated member which is alone provided for the advancement of the magazine and which has a portion thereof projecting from the hand-grip portion of the tool casing.

2. A cartridge-actuated fastener-driving tool as claimed in claim 1, in which said transfer means comprises a sleeve member which is open at each end and surrounds the magazine and which is mounted for limited axial displacement in the lower part of the feed channel, one end of said sleeve member normally projecting outwardly from the hand-grip portion of the tool casing to a distance substantially equal to the feed stroke of the magazine.

3. A cartridge-actuated fastener-driving tool as claimed in claim 2, which includes first spring means mounted in the hand-grip portion of the casing and against the force of which the displacement of the sleeve member is effected, and second spring means engageable with said detent means and fixed relative to the other end of the sleeve member within the handgrip portion of the casing.

4. A cartridge-actuated fastener-driving tool as claimed in claim 3, in which said first spring means comprises a helical compression spring mounted in the feed channel and which is seated at its one end against a shoulder in the feed channel and is supported at its other end at the said other end of the sleeve member.

5. A cartridge-actuated fastener-driving tool as claimed in claim 4, in which said second spring means is formed as an extension of said first spring means by said helical compression spring being bent first radially outwardly and then axially up to and beyond the inner end of said compression spring.

6. A cartridge-actuated fastener-driving tool as claimed in claim 4, in which said second spring means is a spring strip element having its outer end bent inwardly and clamped between the sleeve member and the helical compression spring.

7. A cartridge-actuated fastener-driving tool as claimed in claim 2, in which a recess is provided in said sleeve member and a check pin is secured to the handgrip portion of the tool casing to project into said recess, said check pin acting to limit the feed stroke of the sleeve member.

8. A cartridge-actuated fastener-driving tool as claimed in claim 1, in which a spring clip projects into the upper end of the feed channel to engage said detent means and preventing reverse movement of the magazine, said spring clip being mounted in a recess in the tool casing.

9. A cartridge-actuated fastener-driving tool as claimed in claim 1, which includes arrester means secured in the tool casing and projecting through a longitudinal slot in the barrel to limit forward movement of the plunger, said arrester means being arranged to be removable so that it can be replaced by arrester means having a different profile at the end thereof projecting into the track of the plunger in order to provide for variation of the size of the expansion chamber between the cartridge chamber and the head of the plunger. 

1. A cartridge-actuated fastener-driving tool comprising a tool casing, a barrel which is axially displaceable in the casing and which carries a plunger which is arranged to be explosively thrust down the barrel to drivingly insert a fastener, a cartridge chamber at the rear end of the barrel on the axis thereof, a breech member mounted in the tool casing adjacent to the cartridge chamber, firing pin means within the breech member and movable relative thereto, a magazine feed channel extending through a hand-grip portion of the tool casing and between the rear end of the barrel and the breech member, said feed channel being arranged to receive a strip-form magazine loaded with cartridges arranged serially in succession along the strip, the magazine being provided with a plurality of detent means spaced along its length at distances equal to the cartridge spacing, and displaceable transfer means engageable with said detent means in order to advance the magazine in step-wise manner through the feed channel, said transfer means being formed as a manually actuated member which is alone provided for the advancement of the magazine and which has a portion thereof projecting from the hand-grip portion of the tool casing.
 2. A cartridge-actuated fastener-driving tool as claimed in claim 1, in which said transfer means comprises a sleeve member which is open at each end and surrounds the magazine and which is mounted for limited axial displacement in the lower part of the feed channel, one end of said sleeve member normally projecting outwardly from the hand-grip portion of the tool casing to a distance substantially equal to the feed stroke of the magazine.
 3. A cartridge-actuated fastener-driving tool as claimed in claim 2, which includes first spring means mounted in the hand-grip portion of the casing and against the force of which the displacement of the sleeve member is effected, and second spring means engageable with said detent means and fixed relative to the other end of the sleeve member within the hand-grip portion of the casing.
 4. A cartridge-actuated fastener-driving tool as claimed in claim 3, in which said first spring means comprises a helical compression spring mounted in the feed channel and which is seated at its one end against a shoulder in the feed channel and is supported at its other end at the said other end of the sleeve member.
 5. A cartridge-actuated fastener-driving tool as claimed in claim 4, in which said second spring means is formed as an extension of said first spring means by said helical compression spring being bent first radially outwardly and then axially up to and beyond the inner end of said compression spring.
 6. A cartridge-actuated fastener-driving tool as claimed in claim 4, in which said second spring means is a spring strip element having its outer end bent inwardly and clamped between the sleeve member and the helical compression spring.
 7. A cartridge-actuated fastener-driving tool as claimed in claim 2, in which a recess is provided in said sleeve member and a check pin is secured to the hand-grip portion of the tool casing to project into said recess, said check pin acting to limit the feed stroke of the sleeve member.
 8. A cartridge-actuated fastener-driving tool as claimed in claim 1, in which a spring clip projects into the upper end of the feed channel to engage said detent means and preventing reverse movement of the magazine, said spring clip being mounted in a recess in the tool casing.
 9. A cartridge-actuated fastener-driving tool as claimed in claim 1, which includes arrester means secured in the tool casing and projecting through a longitudinal slot in the barrel to limit forward movement of the plunger, said arrester means being arranged to be removable so that it can be replaced by arrester means having a different profile at the end thereof projecting into the track of the plunger in order to Provide for variation of the size of the expansion chamber between the cartridge chamber and the head of the plunger. 